The aim of this study was to determine the average penile length of a group of healthy, young Turkish men, and to investigate the relationship between penile length and somatometric parameters in the same group. The flaccid and stretched length and circumference of the penis was measured in a group of 2276 physically normal, young men. The correlation between penile length and weight, height and body mass index (BMI) of the participants was determined by Pearson's analysis. The mean age of the participants was 21.1 ± 3.1 (18-39) years. The mean flaccid, fully stretched and circumferential length of the participants' penises were 8.95 ± 1.04, 13.98 ± 1.58 and 8.89 ± 0.86 cm, respectively. There was a significant relationship between all of these variables (P<0.01). Although weak positive correlations were found between the mean circumference length and BMI, there were no correlations between both the flaccid and stretched lengths and BMI. The penile length must be known to be able to determine the abnormal penile sizes and to make convenient decisions in the counseling and/or treatment of people with short penis concerns. Our study provides mean penile lengths in a large sample of healthy, young Turkish men, and the penile dimensions were found to be weakly correlated with somatometric parameters.